Sectional flooring

ABSTRACT

Disclosed is a sectional flooring capable of making the horizontal assemblage as well as the inclined assemblage without removing the stopper, and fluently conducting the assembling operation without the interference or the breakage of the stopper while reinforcing the coupling between the floor boards. The sectional flooring has a floor board with first and second coupling structures at the lateral sides thereof. The first coupling structure has a protrusion, a prominence connected to the bottom of the protrusion while being bulged opposite to the top surface of the floor board, and a stopper receiving indentation indented from the end of the protrusion to the inside of the floor board. The second coupling structure has a groove, a depression connected to the bottom of the groove while being hollowed toward the bottom surface of the floor board, and a stopper protruded from the end of the depression to the outside of the floor board. The protrusion and the groove have inclined upper sides directed toward the top surface of the floor board with an inclination of 10-30° with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the floor board.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a sectional flooring, and in particular, to a sectional flooring which has separate floor boards each with a coupling structure at the lateral sides thereof to be mechanically coupled to its neighbors thereby.

(b) Description of Related Art

Generally, a sectional flooring is formed with a plurality of floor boards each having a predetermined dimension, which is made separately, and assembled together to be installed on the floor of a building. The respective floor boards are formed with a rectangular plane shape, and have a coupling structure at the lateral sides thereof.

With the conventional sectional flooring, protrusions and grooves are formed at the lateral sides of the floor boards contacting each other, respectively. The two floor boards are assembled with each other using the protrusions and the grooves, and fixed to the building floor using an adhesive or nails. However, with such a fixation technique, it is difficult to remove the floor boards, and an epoxy-based adhesive harmful to the human body should be used to make the fixation.

It has been proposed that an adhesive should be applied to the lateral sides of the floor boards with protrusions and grooves to simultaneously utilize the mechanical assemblage and the adhesive-based adhesion force. As the sectional flooring is not fixed to the building floor with such a fixation technique, it is called a suspension type, and involves an advantage of easily making the installation and the removal of the floor boards. However, in case the adhesive is frozen, or used after the long-termed storage, it cannot give a sufficient adhesion force, and in case the adhesive is not properly applied to the floor boards, a gap or a stepped difference may be made between the floor boards.

Among the suspension typed structures, a locking member may be formed at the lateral sides of the floor boards without using the adhesive. In this connection, WO 97/47834 discloses a sectional flooring, and WO 01/48332A1 discloses a panel with a plug-in sectional shape.

Meanwhile, when the floor boards with a locking member are installed, the assembling of the floor boards is made while inclining one of the floor boards. Furthermore, in case a doorsill or other barriers are installed while making it difficult to conduct the inclined assemblage, the floor boards are assembled together while being placed at the same horizontal plane. However, when the horizontal assemblage is applied to the conventional sectional flooring, the locking member is liable to be damaged, or it becomes impossible to make the horizontal assemblage.

FIG. 14 is a partial sectional view of a sectional flooring disclosed in WO 97/47834.

As shown in FIG. 14, when a first floor board 120 with a groove 121 is horizontally assembled with a second floor board 130 with a protrusion 131, a stopper 122 of the first floor board 120 is bent downwards such that the protrusion 131 of the second floor board 130 is fluently inserted into the groove 121 of the first floor board 120. However, in case the elasticity of the first and the second floor boards 120 and 130 is low or the protrusion 131 is inserted into the groove 121 by applying a momentous impact thereto, a crack (indicated by the dotted line) is liable to be made at the lateral side of the first floor board 120 with the groove 121. Such a crack may induce a stepped difference between the assembled floor boards, and weaken the adhesion force thereof while making a gap therebetween.

FIG. 15 is a partial sectional view of a sectional flooring disclosed in WO 01/48332A1.

As shown in FIG. 15, when a second floor board 150 horizontally proceeds toward a first floor board 140 to make the assemblage thereof, as the first floor board 140 has a high stopper 141, the lateral side of a lower-sided protrusion 151 of the second floor board 150 is stopped by the stopper 141. When the second floor board 150 is forcefully pressurized against the first floor board 140 to make the horizontal assemblage thereof, the stopper 141 may be broken (as indicated by the dotted line). In this case, the stopper 141 should be partially removed using a knife or a plane, but this involves inconvenient installation, and may weaken the coupling between the first and the second floor boards 140 and 150 after the assembling thereof.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a sectional flooring which enables the horizontal assemblage as well as the inclined assemblage without removing the stopper, and fluently makes the assembling operation without the interference or the breakage of the stopper while reinforcing the coupling between the floor boards.

This and other objects may be achieved by a sectional flooring with the following features.

According to one aspect of the present invention, the sectional flooring has a floor board with top and bottom surfaces and four lateral sides. The floor board includes a first coupling structure formed at one of the lateral sides of the floor board, and a second coupling structure formed at another lateral side of the floor board. The first coupling structure has a protrusion, a prominence connected to the bottom of the protrusion while being bulged opposite to the top surface of the floor board, and a stopper receiving indentation indented from the end of the protrusion to the inside of the floor board. The second coupling structure has a groove, a depression connected to the bottom of the groove while being hollowed toward the bottom surface of the floor board, and a stopper protruded from the end of the depression to the outside of the floor board. The protrusion and the groove have inclined upper sides directed toward the top surface of the floor board with an inclination of 10-30° with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the floor board.

The second coupling structure further has a middle stopper protruded toward the top surface of the floor board between the groove and the depression, and the first coupling structure further has a middle stopper receiving indentation indented toward the top surface between the protrusion and the prominence.

According to another aspect of the present invention, the sectional flooring has a floor board with top and bottom surfaces and four lateral sides. The floor board includes a first coupling structure formed at one of the lateral sides of the floor board, and a second coupling structure formed at another lateral side of the floor board. The first coupling structure has a protrusion, a lower stopper receiving indentation connected to the bottom of the protrusion and indented toward the top surface of the floor board, and an upper stopper receiving indentation indented from the end of the lower stopper receiving indentation toward the top surface of the floor board. The second coupling structure has a groove, a lower stopper connected to the bottom of the groove and protruded opposite to the bottom surface of the floor board, and an upper stopper protruded from the end of the lower stopper opposite to the bottom surface of the floor board. The protrusion and the groove have inclined upper sides directed toward the top surface of the floor board with an inclination of 10-30° with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the floor board.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other advantages of the present invention will become more apparent by describing preferred embodiments thereof in detail with reference to the accompanying drawings in which:

FIG. 1 is a partial sectional perspective view of a floor board of a sectional flooring according to a first embodiment of the present invention;

FIG. 2 is a plan view of the floor board of the sectional flooring according to the first embodiment of the present invention;

FIG. 3 is a partial sectional view of the floor boards of the sectional flooring according to the first embodiment of the present invention, illustrating the pre-assemblage state thereof;

FIGS. 4 to 7 are partial sectional views of the floor boards of the sectional flooring according to the first embodiment of the present invention, illustrating the process of assembling them;

FIG. 8 is a partial sectional view of the floor boards of the sectional flooring according to the first embodiment of the present invention, illustrating the imagined case where the contact sides of the floor boards are applied with a vertical load directed upwards;

FIG. 9 is a partial sectional view of floor boards of a sectional flooring according to a second embodiment of the present invention, illustrating the pre-assemblage state thereof;

FIG. 10 is a partial sectional view of the floor boards of the sectional flooring according to the second embodiment of the present invention, illustrating the post-assemblage state thereof;

FIG. 11 is a partial sectional view of floor boards of a sectional flooring according to a third embodiment of the present invention, illustrating the post-assemblage state thereof;

FIG. 12 is a partial sectional view of floor boards of a sectional flooring according to a fourth embodiment of the present invention, illustrating the pre-assemblage state thereof;

FIG. 13 is a partial sectional view of the floor boards of the sectional flooring according to the fourth embodiment of the present invention, illustrating the post-assemblage state thereof; and

FIGS. 14 and 15 are partial sectional views of floor boards of sectional floorings according to prior arts.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown.

FIG. 1 is a partial sectional perspective view of a floor board of a sectional flooring according to a first embodiment of the present invention, and FIG. 2 is a plan view of the floor board.

As shown in the drawings, the floor board 1 has a first coupling structure 10 formed at a lateral side thereof, and a second coupling structure 20 at another lateral side. The first coupling structure 10 has a protrusion 11, a prominence 12, and a stopper receiving indentation 13. The second coupling structure 20 has a groove 21, a depression 22, and a stopper 23. The floor board 1 is assembled to floor board neighbors thereof (not shown) at its lateral sides through the first and the second coupling structures 10 and 20.

When viewed from the plan side, the floor board 1 has a rectangular-shaped plane with a pair of longitudinal sides and a pair of latitudinal sides. The first coupling structure 10 of the floor board 1 is formed at one of the longitudinal sides and one of the latitudinal sides, and the second coupling structure 20 is formed at the other longitudinal side and the other latitudinal side.

FIG. 3 is a partial sectional view of first and second floor boards of the sectional flooring according to the first embodiment of the present invention, illustrating the pre-assemblage state thereof. The first floor board 30 has a first coupling structure at its one side, and the second floor board 40 has a second coupling structure at its one side.

As shown in FIG. 3, the first coupling structure has a protrusion 11 protruded to the outside of the first floor board 30 in the direction of the plane of the first floor board 30 (in the direction of the X axis of FIG. 3) while being spaced apart from a top surface 31 of the first floor board 30 with a distance, a prominence 12 connected to the bottom of the protrusion 11 and bulged in the direction of the thickness of the first floor board 30 (in the direction of the Z axis of FIG. 3), and a stopper receiving indentation 13 indented from the end of the protrusion 12 to the inside of the first floor board 30.

The second coupling structure has a groove 21 grooved to the inside of the second floor board 40 in the direction of the plane of the second floor board 40 (in the direction of the X axis of FIG. 3) while being spaced apart from the top surface 41 of the second floor board 40 to receive the protrusion 11 of the first floor board 30, a depression 22 connected to the bottom of the groove 21 while being hollowed toward a bottom surface 42 of the second floor board 40 in the direction of the thickness of the second floor board 40 (in the direction of the Z axis of FIG. 3) to receive the prominence 12 of the first floor board 30, and a stopper 23 protruded from the end of the depression 22 opposite to the bottom surface 42 of the second floor board 40 and inserted into the stopper receiving indentation 13 of the first floor board 30.

The first floor board 30 has a first contact surface 14 formed between the top surface 31 and the protrusion 11 while proceeding parallel to the direction of the thickness thereof, and the second floor board 40 has a second contact surface 24 formed between the top surface 41 and the groove 21 while proceeding parallel to the direction of the thickness thereof. When the first and the second floor boards 30 and 40 are assembled with each other, the two contact surfaces 14 and 24 contact each other.

The protrusion 11 has an inclined upper side connected to the first contact surface 14, and the groove 21 also has an inclined upper side connected to the second contact surface 24. The inclined sides become gradually distant from the top surfaces 31 and 41 as they go farther from the first and the second contact surfaces 14 and 24. When an imaginary rectilinear line (illustrated by the dotted line) is drawn parallel to the direction of the plane of the first and the second floor boards 30 and 40, the inclination of the inclined upper sides of the protrusion 11 and the groove 21 with respect to the imaginary line is established to be 10-30°. When the first and the second floor boards 30 and 40 are assembled with each other, the inclined sides of the protrusion 11 and the groove 21 guide the protrusion 11 to the inside of the groove 21.

The second floor board 40 has a middle stopper 25 formed between the groove 21 and the depression 22 while being protruded toward the top surface 41 in the direction of the thickness thereof, and the first floor board 30 has a middle stopper receiving indentation 15 formed between the protrusion 11 and the prominence 12 while being indented toward the top surface 31. The middle stopper 25 of the second floor board 40 is inserted into the middle stopper receiving indentation 15.

The prominence 12 has a lower inclined side, and the stopper 23 has an upper inclined side 23 a. The inclined lower side of the prominence 12 is structured such that the distance between the lower side of the prominence 12 and the top surface 31 of the first floor board 30 becomes reduced as the lower side of the prominence 12 goes closer to the groove 21. The inclined upper side 23 a of the stopper 23 guides the lower side of the prominence 12 such that the first floor board 30 fluently proceeds toward the second floor board 40.

FIGS. 4 to 7 are partial sectional views of the first and the second floor boards of the sectional flooring, illustrating the process of assembling them together.

As shown in FIG. 4, when the lateral side of the first floor board 30 with the protrusion 11 moves toward the lateral side of the second floor board 40 with the groove 21 in the arrow direction, the lower side of the prominence 12 of the first floor board 30 contacts the inclined upper side 23 a of the stopper 23 of the second floor board 40. In this process, due to the inclination of the lower side of the prominence 12 and the inclination of the inclined upper side 23 a of the stopper 23, the lower side of the prominence 12 guides along the inclined upper side 23 a of the stopper 23 so that the first floor board 30 is slightly elevated till the protrusion 11 of the first floor board 30 contacts the groove 21 of the second floor board 40.

As shown in FIG. 5, the protrusion 11 of the first floor board 30 contacts the groove 21 of the second floor board 40 (indicated by the circular dotted line) due to the movement of the first floor board 30, the inclined upper side of the groove 21 guides the inclined upper side of the protrusion 11 due to the inclination thereof. Consequently, as shown in FIG. 6, the protrusion 11 moves toward the bottom surface 42 of the second floor board 40, and is inserted into the groove 21.

The protrusion 11 of the first floor board 30 moves toward the bottom surface 42 of the second floor board 40 along the inclined upper side of the groove 21 such that the protrusion 11 and the prominence 12 wholly ride over the stopper 23 of the second floor board 40. That is, when the protrusion 11 moves toward the bottom surface 42 of the second floor board 40 along the inclined upper side of the groove 21, the prominence 12 rides on the stopper 23 upwards, and then goes downwards. Consequently, the prominence 11 is safely mounted at the depression 22 without the interference of the stopper 23 (conveniently, the up and down movement of the prominence 12 called a ‘jumping effect’).

As shown in FIG. 7, the first and the second contact surfaces 14 and 24 contact each other, and the middle stopper 25 of the second floor board 40 is inserted into the middle stopper receiving indentation 15 of the first floor board 30, thereby completing the assemblage of the first and the second floor boards 30 and 40. In this process, the horizontal assemblage of the first and the second floor boards 30 and 40 is made without the interference of the stopper 23 or the breakage thereof. The horizontal surface of the middle stopper 25 fluently guides the prominence 12 when the protrusion 11 of the first floor board 30 is inserted into the groove 21 with a predetermined inclination.

When the protrusion 11 and the prominence 12 of the first floor board 30 ride over the stopper 23 of the second floor board 40, the inclination of the first floor board 30 with respect to the second floor board 40 does not exceed 100, and hence, the horizontal assemblage of the first and the second floor boards 30 and 40 can be easily made for a short period of time while minimizing the interference of the stopper 23 or the breakage thereof.

The jumping effect of the prominence 12 of the first floor board 30 is due to the fact that when an imaginary rectilinear line is drawn parallel to the direction of the plane of the first and the second floor boards 30 and 40 (as indicated by the dotted line of FIG. 3), the inclined upper sides of the protrusion 11 and the groove 21 with respect to the imaginary rectilinear line has an inclination θ of 10-30°.

When the inclination exceeds 30°, the jumping effect of the prominence 12 becomes greater such that the horizontal assemblage of the first and the second floor boards 30 and 40 can be made easily, but the possibility of inducing a stepped difference between the first and the second floor boards 30 and 40 becomes heightened. By contrast, when the inclination is less than 10°, the jumping effect of the prominence 12 and the guiding effect of the protrusion 11 and the groove 21 due to inclination of the upper sides thereof cannot be expected, and when the first floor board 30 proceeds toward the second floor board 40, it may interfere with the stopper 23.

Meanwhile, the sectional flooring according to the present embodiment has a structure well adapted for the under floor heating system. That is, in case the floor of the building to be installed with the sectional flooring is heated at high temperature, the bottom surface of the flooring directly contacting the building floor is shrunk due to the heat after the long period of time passes by. In this case, as shown in FIG. 8, the coupling between the first and the second floor boards 30 and 40 suffers a vertical load directed upwards, and is liable to be broken where the stress is concentrated, or a gap may be made there.

However, with the sectional flooring according to the present embodiment, the stress is bifurcated into the contact area of the upper sides of the protrusion 11 and the groove 21 (indicated by the circular dotted line A) and the contact area of the middle stopper 25 and the middle stopper receiving indentation 15 (indicated by the circular dotted line B), the breakage of the coupling structure and the gap formation due to the concentrated stress can be minimized.

FIG. 9 is a partial sectional view of a sectional flooring according to a second embodiment of the present invention, illustrating the pre-assemblage state thereof, and FIG. 10 is a partial sectional view of the sectional flooring, illustrating the post-assemblage state thereof.

As shown in the drawings, the sectional flooring according to the present embodiment has the same basic structure as that related to the first embodiment except that a lateral side 23 b of the stopper 23 connected to the depression 22 and a lateral side 12 a of the prominence 12 connected to the stopper receiving indentation 13 are differentiated in the inclination thereof to reinforce the coupling between the stopper 23 and the prominence 12.

Assume that an imaginary rectilinear line is drawn parallel to the direction of the plane of the first and the second floor boards 50 and 60. When the inclination of the lateral side 12 a of the prominence 12 connected to the stopper receiving indentation 13 with respect to the imaginary rectilinear line is θ 1, and the inclination of the lateral side 23 b of the stopper 23 connected to the depression 22 with respect to the imaginary rectilinear line is θ 2, the first and the second floor boards 50 and 60 are structured to satisfy the following condition. θ 2=θ 1+a, a=1˜5°  (1)

The first and the second floor boards 50 and 60 may be formed with a wood fiber plate with the properties of compression and elasticity, which is made by pressurizing and heating a wood fiber, and press-forming it.

With the above structure, when the protrusion 11 of the first floor board 50 is inserted into the groove 21 of the second floor board 60, the lateral side 23 b of the stopper 23 of the second floor board 60 is pressurized against the lateral side 12 a of the prominence 12 of the first floor board 50. Consequently, even if the contact area between the prominence 12 and the stopper 23 is shrunk by heat, the contacting between the stopper 23 and the prominence 12 can be maintained, thereby minimizing the weakness in the coupling between the first and the second floor boards 50 and 60, and inhibiting the gap formation therebetween.

FIG. 11 is a partial sectional view of floor boards of a sectional flooring according to a third embodiment of the present invention, illustrating the post-assemblage state thereof.

As shown in FIG. 11, the sectional flooring according to the present embodiment has the same basic structure as that related to the first embodiment except that when the first and the second floor boards 70 and 40 are assembled with each other or disassembled from each other, the elasticity of the protrusion 11 and the prominence 12 is heightened. For this purpose, when the thickness of the first floor board 70 is assumed to be t, and the distance between the top surface 71 of the first floor board 70 and the stopper receiving indentation 13′ measured in the direction of the thickness thereof to be c, the following condition should be satisfied. 0.25≦c/t≦0.40   (2)

When the value of c with respect to the thickness t of the first floor board 70 is less than 0.25, the elasticity of the protrusion 11 and the prominence 12 is heightened, but a crack is liable to be made at the stopper receiving indentation 13′. By contrast, when the value of c with respect to the thickness t of the first floor board 70 exceeds 0.40, it cannot be expected for the protrusion 11 and the prominence 12 to have a sufficient elasticity.

Like the above, with the floor board according to the present embodiment, as the value of c is reduced, the elasticity of the protrusion 11 and the prominence 12 provided at the first floor board 70 is heightened such that the operation of assembling or disassembling the first and the second floor boards 70 and 40 can be conducted easily. Furthermore, with the sectional flooring according to the present embodiment, when the floor boards are distorted due to the ambient temperature or humidity, the stress generated at the coupling structure with the protrusion 11 and the groove 21 is diffused around the stopper receiving indentation 13′, thereby minimizing the distortion of the coupling structure.

FIG. 12 is a partial sectional view of a sectional flooring according to a fourth embodiment of the present invention, illustrating the pre-assemblage state thereof, and FIG. 13 is a partial sectional view of the sectional flooring, illustrating the post-assemblage state thereof.

As shown in the drawings, the first floor board 80 according to the present embodiment has a first coupling structure 90 at its one side, and the second floor board 100 has a second coupling structure 110 at its one side. The first coupling structure 90 has a protrusion 91 protruded to the outside of the first floor board 80 in the direction of the plane of the first floor board 80 (in the direction of the X axis of the drawing), a lower stopper receiving indentation 92 connected to the bottom of the protrusion 91 while being indented toward the top surface 81 in the direction of the thickness of the first floor board 80 (in the direction of the Z axis of the drawing), and an upper stopper receiving indentation 93 indented from the end of the lower stopper receiving indentation 92 toward the top surface 81 of the first floor board 80.

The second coupling structure 110 has a groove 111 grooved to the inside of the second floor board 100 in the direction of the plane of the second floor board 100 to receive the protrusion 91 of the first floor board 80, a lower stopper 112 connected to the bottom of the groove 111 while being protruded opposite to the bottom surface 102 in the direction of the thickness of the second floor board 100 to be inserted into the lower stopper receiving indentation 92, and an upper stopper 113 protruded from the end of the lower stopper 112 opposite to the bottom surface 102 of the second floor board 100 to be inserted into the upper stopper receiving indentation 93 of the first floor board 80.

The protrusion 91 has an inclined upper side directed toward the top surface 81 of the first floor board 80, and the groove 111 also has an inclined upper side directed toward the top surface 101 of the second floor board 100. The inclined sides are angled against an imaginary line (indicated by the dotted line of the drawing) proceeding parallel to the direction of the plane of the first and the second floor boards 80 and 100 preferably with an inclination θ of 10-30°. When the protrusion 81 of the first floor board 80 is inserted into the groove 111 of the second floor board 100, the inclined sides of the protrusion 91 and the groove 81 guide the protrusion 91 to the inside of the groove 111, thereby making the inclined assemblage and the horizontal assemblage between the two floor boards 80 and 100 easy.

The lower stopper receiving indentation 92 has an inclined lateral side 92 a connected to the bottom of the protrusion 91, and the lower stopper 112 also has an inclined lateral side 112 a connected to the bottom of the groove 111. The inclined sides guide the bottom of the protrusion 91 to the bottom of the groove 111, thereby making the assemblage of the protrusion 91 and the groove 111 fluent. With the inclined assemblage of the first and the second floor boards 80 and 100, the lower stopper 112 of the second floor board 100 makes the rotation of the protrusion 91 fluent. After the assembling of the first and the second floor boards 80 and 100, the inclined lateral side 112 a of the lower stopper 112 and the inclined lateral side 92 a of the lower stopper receiving indentation 92 are spaced apart from each other by a distance of 0.1-0.2 mm.

The upper stopper receiving indentation 93 has an inclined lateral side 93 a connected to the lower stopper receiving indentation 92, and the upper stopper 113 also has an inclined lateral side 113 a connected to the lower stopper 112. When the inclination of the inclined lateral side 93 a of the upper stopper receiving indentation 93 connected to the lower stopper receiving indentation 92 with respect to an imaginary rectilinear line (indicated by the dotted line) proceeding parallel to the plane of the first and the second floor boards 80 and 100 is assumed to be θ 3, and the inclination of the inclined lateral side 113 a of the upper stopper 113 connected to the lower stopper 112 with respect to the imaginary line to be θ 4, the first and the second floor boards 80 and 100 are structured to satisfy the following condition. θ 4=θ 3+a, a=1˜5°  (3)

As like the structure related to the second embodiment, the first and the second floor boards 80 and 100 may be formed with a wood fiber plate with the properties of compression and elasticity, which is made by pressurizing and heating a wood fiber, and press-forming it.

With the above structure, when the protrusion 91 of the first floor board 80 is inserted into the groove 111 of the second floor board 100, the inclined lateral side 113 a of the upper stopper 113 of the second floor board 100 strongly pressurizes the inclined lateral side 93 a of the upper stopper receiving indentation 93 of the first floor board 80, thereby heightening the interconnection strength between the floor boards 80 and 100. Consequently, even if the contact area between the upper stopper 113 and the upper stopper receiving indentation 93 is shrunk by heat, the contacting thereof can be maintained, thereby preventing the loosening and the gap formation of the floor boards effectively.

Like the above, with the sectional flooring according to the present embodiment, as the second floor board 100 has a double stopper structure with an upper stopper 112 and a lower stopper 113, the horizontal assemblage between the first and the second floor boards 80 and 100 can be made easily with the low height of the upper stopper 113, and the stoppers 112 and 113 reinforce the coupling between the first and the second floor boards 80 and 100, thereby heightening the coupling endurance thereof.

As described above, with the inventive sectional flooring, the horizontal assemblage of the floor boards thereof can be made fluently with no removal of the stopper without interfering with the stopper and inducing the breakage thereof. In this way, the coupling between the floor boards is reinforced, and the breakage or gap formation of the coupling structure can be minimized even when the building floor is heated at high temperature.

With the above structure, the horizontal assemblage of the floor board neighbors of the sectional flooring can be made fluently without interfering with the stopper or inducing the breakage thereof, thereby heightening the workability. Furthermore, as the coupling between the floor boards is reinforced, the distortion of the floor boards or the gap formation due to the ambient temperature or humidity can be minimized, thereby enhancing the quality of the sectional flooring.

Although preferred embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that many variations and/or modifications of the basic inventive concept herein taught which may appear to those skilled in the art will still fall within the spirit and scope of the present invention, as defined in the appended claims. 

1. A sectional flooring having a floor board with top and bottom surfaces and four lateral sides, the floor board comprising: a first coupling structure formed at one of the lateral sides of the floor board, the first coupling structure having a protrusion, a prominence connected to the bottom of the protrusion while being bulged opposite to the top surface of the floor board, and a stopper receiving indentation indented from the end of the protrusion to the inside of the floor board; and a second coupling structure formed at another lateral side of the floor board, the second coupling structure having a groove, a depression connected to the bottom of the groove while being hollowed toward the bottom surface of the floor board, and a stopper protruded from the end of the depression to the outside of the floor board; wherein the protrusion and the groove have inclined upper sides directed toward the top surface of the floor board with an inclination of 10-30° with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the floor board.
 2. The sectional flooring of claim 1 wherein the second coupling structure further has a middle stopper protruded toward the top surface of the floor board between the groove and the depression, and the first coupling structure further has a middle stopper receiving indentation indented toward the top surface between the protrusion and the prominence.
 3. The sectional flooring of claim 1 wherein the prominence has an inclined lower side, and the stopper has an upper side inclined in the inclining direction of the inclined lower side of the prominence.
 4. The sectional flooring of claim 1 wherein the prominence has an inclined lateral side connected to the stopper receiving indentation, and the stopper has an inclined lateral side connected to the depression, the inclination of the inclined lateral side of the stopper with respect to an imaginary rectilinear line proceeding parallel to the plane of the floor board being greater than the inclination of the inclined lateral side of the prominence with respect to the imaginary rectilinear line.
 5. The sectional flooring of claim 4 wherein when the inclination of the inclined lateral side of the prominence with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the floor board is θ 1, and the inclination of the inclined lateral side of the stopper with respect to the imaginary rectilinear line is θ 2, the floor board satisfies the following condition: θ 2=θ 1+a, a=1∫5°.
 6. The sectional flooring of claim 1 wherein when the thickness of the floor board is assumed to be t, and the distance between the top surface of the floor board and the stopper receiving indentation measured in the direction of the thickness of the floor board to be c, the floor board satisfies the following condition: 0.25≦c/t≦0.40.
 7. A sectional flooring having a floor board with top and bottom surfaces and four lateral sides, the floor board comprising: a first coupling structure formed at one of the lateral sides of the floor board, the first coupling structure having a protrusion, a lower stopper receiving indentation connected to the bottom of the protrusion and indented toward the top surface of the floor board, and an upper stopper receiving indentation indented from the end of the lower stopper receiving indentation toward the top surface of the floor board; and a second coupling structure formed at another lateral side of the floor board, the second coupling structure having a groove, a lower stopper connected to the bottom of the groove and protruded opposite to the bottom surface of the floor board, and an upper stopper protruded from the end of the lower stopper opposite to the bottom surface of the floor board; wherein the protrusion and the groove have an inclined upper side with an inclination of 10-30° with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the floor board.
 8. The sectional flooring of claim 7 wherein the lower stopper receiving indentation has an inclined lateral side connected to the bottom of the protrusion, and the lower stopper has an inclined lateral side connected to the bottom of the groove.
 9. The sectional flooring of claim 7 wherein the upper stopper receiving indentation has an inclined lateral side connected to the lower stopper receiving indentation, and the upper stopper has an inclined lateral side connected to the lower stopper, the inclination of the inclined lateral side of the upper stopper with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the floor board being greater than the inclination of the inclined lateral side of the upper stopper receiving indentation with respect to the imaginary rectilinear line.
 10. The sectional flooring of claim 9 wherein when the inclination of the inclined lateral side of the upper stopper receiving indentation with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the floor board is assumed to be θ 3, and the inclination of the inclined lateral side of the upper stopper with respect to the imaginary line to be θ 4, the floor board satisfies the following condition: θ 4=θ 3+a, a=1˜5°.
 11. The sectional flooring of claim 7 wherein the floor board has a pair of longitudinal sides and a pair of latitudinal sides, and the first coupling structure is formed at one of the longitudinal sides and one of the latitudinal sides while the second coupling structure being formed at the other longitudinal side and the other latitudinal side.
 12. The sectional flooring of claim 9 wherein the floor board is formed with a material having the properties of compression and elasticity.
 13. The sectional flooring of claim 12 wherein the floor board is formed with a wood fiber plate made by press-forming a wood fiber at a given temperature under a given pressure.
 14. A sectional flooring comprising: a first floor board; a first coupling structure formed at a lateral side of the first floor board, the first coupling structure having a protrusion, a prominence connected to the bottom of the protrusion and bulged opposite to the top surface of the first floor board, and a stopper receiving indentation indented from the end of the prominence to the inside of the first floor board; a second floor board assembled to the first floor board; and a second coupling structure formed at a lateral side of the second floor board, the second coupling structure having a groove receiving the protrusion, a depression connected to the bottom of the groove and hollowed toward the bottom surface of the second floor board to receive the prominence, and a stopper protruded from the end of the depression to the outside of the second floor board and inserted into the stopper receiving indentation; wherein the protrusion and the groove have inclined upper sides directed toward the top surfaces of the first and the second floor boards with an inclination of 10-30° with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the first and the second floor boards.
 15. The sectional flooring of claim 14 wherein the coupling structure of the second floor board further has a middle stopper protruded toward the top surface of the second floor board between the groove and the depression, and the coupling structure of the first floor board further has a middle stopper receiving indentation indented toward the top surface of the first floor board between the protrusion and the prominence.
 16. The sectional flooring of claim 14 wherein the prominence has an inclined lower side, and the stopper has an upper side inclined in the inclining direction of the inclined lower side of the prominence.
 17. The sectional flooring of claim 14 wherein the prominence has an inclined lateral side connected to the stopper receiving indentation, and the stopper has an inclined lateral side connected to the depression, the inclination of the inclined lateral side of the stopper with respect to an imaginary rectilinear line proceeding parallel to the plane of the first and the second floor boards being greater than the inclination of the inclined lateral side of the prominence with respect to the imaginary rectilinear line.
 18. The sectional flooring of claim 17 wherein when the inclination of the inclined lateral side of the prominence with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the first and the second floor boards is θ 1, and the inclination of the inclined lateral side of the stopper with respect to the imaginary rectilinear line is θ 2, the first and the second floor boards satisfy the following condition: θ 2=θ 1+a, a=1˜5°.
 19. The sectional flooring of claim 14 wherein when the thickness of the first floor board is assumed to be t, and the distance between the top surface of the first floor board and the stopper receiving indentation measured in the direction of the thickness of the first floor board to be c, the first floor board satisfies the following condition: 0.25≦c/t≦0.40.
 20. A sectional flooring comprising: a first floor board; a first coupling structure formed at a lateral side of the first floor board, the first coupling structure having a protrusion, a lower stopper receiving indentation connected to the bottom of the protrusion and indented toward the top surface of the first floor board, and an upper stopper receiving indentation indented from the end of the lower stopper receiving indentation toward the top surface of the first floor board; a second floor board assembled to the first floor board; and a second coupling structure formed at a lateral side of the second floor board, the second coupling structure having a groove receiving the protrusion, a lower stopper connected to the bottom of the groove while being protruded opposite to the bottom surface of the second floor board and inserted into the lower stopper receiving indentation, and an upper stopper protruded from the end of the lower stopper opposite to the bottom surface of the second floor board and inserted into the upper stopper receiving indentation; wherein the protrusion and the groove have inclined upper sides directed toward the top surfaces of the first and the second floor boards with an inclination of 10-30° with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the first and the second floor boards.
 21. The sectional flooring of claim 20 wherein the lower stopper receiving indentation has an inclined lateral side connected to the bottom of the protrusion, and the lower stopper has an inclined lateral side connected to the bottom of the groove.
 22. The sectional flooring of claim 20 wherein the upper stopper receiving indentation has an inclined lateral side connected to the lower stopper receiving indentation, and the upper stopper has an inclined lateral side connected to the lower stopper, the inclination of the inclined lateral side of the upper stopper with respect to an imaginary rectilinear line proceeding parallel to the direction of the plane of the first and the second floor boards being greater than the inclination of the inclined lateral side of the upper stopper receiving indentation with respect to the imaginary rectilinear line.
 23. The sectional flooring of claim 22 wherein when the inclination of the inclined lateral side of the upper stopper receiving indentation with respect to an imaginary rectilinear line proceeding parallel to the plane of the first and the second floor boards is assumed to be θ 3, and the inclination of the inclined lateral side of the upper stopper with respect to the imaginary rectilinear line to be θ 4, the first and the second floor boards satisfy the following condition: θ 4=θ 3+a, a=1˜5°.
 24. The sectional flooring of claim 22 wherein the first and the second floor boards are formed with a material having the properties of compression and elasticity.
 25. The sectional flooring of claim 24 wherein the first and the second floor boards are formed with a wood fiber plate made by press-forming a wood fiber at a given temperature under a given pressure. 